Overgirl
by onceuponatime47
Summary: What if, during the Crisis on Earth-X crossover event, the Nazis invaded Supergirl’s Earth, not just Earth 1. How would Mon-El and Winn feel seeing a very evil Kara? Eventual Karamel Includes characters from the other DC shows but Supergirl/Flash centric.
1. chapter 1

**Disclaimer: I do not own an of the DC shows, this is purely for fun.**

Set sometime during the Crisis On Earth-X Crossover Event. This will heavily involve characters from the other shows. I'm staying mostly canon for what has happened during season 3 but I'm taking some creative liberties especially with a certain Daxamite. :)

Please excuse any spelling and grammar errors, this was a bit rushed.

 **Earth 38**

Watching Kara dash off to another Earth was painful as first, but Mon-El realized it was better right now. Every day it got harder and harder for him to pretend to be in love with Imra and not her.

Right now he was hovering over Winn's shoulder, bored half to death. It may be difficult to deal with his feelings, but with Kara gone there was nothing interesting happening. He couldn't help his nerves about the prospect of Kara fighting hordes of Nazis even with a group of superheroes at her side.

Suddenly dazzling blue light erupted int the room. He looked up to see a portal open. His heart thudded. Kara and Alex must be back. The silhouette of a woman materialized and stepped through the portal. Kara. He held back a smile. He frowned slightly, but not a part of his facade. She looked different. Her outfit was different, the symbol on her chest was all wrong. Kara gazed around the room and smiled. An unnerving feeling settled in his stomach. "Kara!" Winn cried out happily. "Where's Alex?"

Kara turned toward Winn and her face twisted into a sneer. "I should have guess there would have been one of you on this Earth." Malice tainted every word.

Ok, it was definitely not his Kara, Mon-El decided. He knew the theory of the multiverse but he had never traveled to another Earth that was so radically different from this one. Not-Kara steps closer to Winn. "Who are you?" He asked, making the connection at the same time as Mon-El.

She tilted back her head with a smile, dangerously regal. "I am a god. I am so much more than your precious Supergirl. If you live long enough to speak, you will call me Overgirl."

"Where is Kara?" Mon-El growled.

Overgirl cocked her head. "I don't know you. Perhaps you died long ago at the hands of the Führer. Supergirl is waiting for me. Or rather, her heart is." She purred.

Before anyone could speak, another figure stepped out of the portal. It was not someone recognized, a bearded man in a hood. He had an arrow slung across his back. Overgirl smiled at him. "My husband, I told you to wait with my lesser counterpart."

Husband? Although this was not the Kara he knew, the word set his skin on fire. The archer whispered words into Overgirl's ear and her smile contorted into anger. "Deal with it." She said

He gave a curt nod and stepped back into the portal. Overgirl took a deep breath and turned her attention back to the room. "Now where were we? Ah, I remember." With a touch of her finger a mask slid up over her face.

The eyes glowed red and Mon-El lunged for Winn. "Get down!"

 **Earth 1**

Dark Arrow's brief disappearance had given Iris and Felicity exactly what they needed to free the others from the meta-human cells. Caitlin has barely taken a foot outside before she became her icy roommate. Mick Rory was eyeing her with something a little more than awe. He'd always had a thing for a cold partner.

 **Sorry for the awkward ending but I definitely have more planned. I know it's super short bit it would be nice if you could leave a comment if you're interested in more. Thanks for taking the time to read! I should have the next chapter posted soon.**


	2. Chapter 2

**Earth 1**

"Ugh!" Cisco shook his head in disgust. "Never thought I would be a prisoner of my own creation. Good to know they work though!"

Iris shot him a steely glance. Cisco held up his hands in defense. Felicity clutched her tablet nervously. "Oli- Dark Arrow will be back soon. He went to Supergirl's Earth, but who knows for how long."

"Where's Sara?" Mick grunted, eating a smooshed sandwich from his coat pocket.

"Shes still on Earth X with Barry, Oliver, and the others. But right now we have on focus on getting Kara and ourselves out of here without getting skewered by Nazi arrows."

"Guys... we might have a problem." Harrison Wells popped back into the room.

"Wells! Where did you go, you could have gotten yourself killed!" Iris said.

He wrinkled his nose with a frown. "Kinda hard to do when we're the only ones here. Kara is gone, and so are all the Nazis."

Felicity gasped. They group rushed to the lab to find it completely empty. All the equipment was still set up, the surgical tools left undisturbed.

Cisco lifted up a thin, clean scalpel. "At least we know Kara is still alive."

"But who knows for how long?" Felicity said. "We need to get the others back from Earth-X."

"Maybe not yet. I have an idea." Killer Frost melted back into Caitlin, much to everyone's relief. "Cisco, I'm going to need your help."

 **Earth 38**

"Get down!"

Red hot lasers burst from Overgirl's eyes. The DEO agents ducked for cover while simultaneously reaching for their weapons to fire back. But just like their own Kara Danvers, bullets did nothing.

Mon-El and Winn had their backs against a hunk of the metal console.

"What do we do?" Winn hissed.

Mon-El racked his brain for ideas. Kara could easily beat him in a fight, and he doubted that Overgirl was any different. He wished Imra and Braniac 5 were here. Maybe together, they could defeat Overgirl. Just one member of the Legion wasn't going to cut it. He looked at Winn. "We need Kryptonite. Do you keep any here?"

The technician winced. "We got rid of most of it. There's some left over. But first we need to get away."

Mon-El nodded and twisted his head to see Overgirl hovering in the center of the room. She had stopped with the heat vision. A DEO agent Winn knew by the name of Connor charged her. She grabbed his neck with ease and threw him back against the wall. Even with the chaos around them, they could hear the snap of the young man's neck.

"On three..." Mon-El said.

The duo counted out loud. On three they climbed to their feet and started to run. It seemed like they had an escape route when another body hit the floor just in front of them.

"Leaving so soon? The party's just getting started." Overgirl laughed.

Mon-El stepped in front of Winn to defend him as Overgirl's eyes glowed scarlet. Before she could get a chance to burn them alive, a shard of glowing metal came whistling past them to burrow in Overgirl's shoulder. It was a dagger. A kryptonite dagger. Overgirl screamed in agony. She grabbed the hilt of the knife and ripped it from her shoulder. She tapped the side of her head to remove the mask. Overgirl fell to her knees with a gasp. Hatred burned in her eyes and green pulsed beneath her veins.

The Nazi Kryptonian stood shakily and ducked back through the portal, it sealed seconds later.

Mon-El and Winn turned to see J'onn J'onzz standing as a Martian behind them. He transformed back into Hank and strode forward to retrieve the dagger. "Boss! Oh, am I glad to see you!" Winn said with relief, raising his arms to hug J'onn.


	3. Chapter 3

**Earth 38**

J'onn patted Winn on the shoulder awkwardly. "Alright, Agent Schott. That's enough."

Winn chucked and took an abrupt step back from the Martian. He ran a hand through his short hair before clapping his hands together loudly. "Okay! Let's focus on what just happened!"

Mon-El nodded, eager to figure out the story behind Kara's evil doppelganger. "She- Overgirl- said something when that archer guy was here-"

"Dark Arrow. Evil Oliver Queen." Winn interrupted. Mon-El gave him a stern look. "Right, not important. Carry on."

"She said that Supergirl was waiting for her. That her heart was waiting."

J'onn frowned. "That doesn't make sense."

Winn shook his head. That he lifted a finger in the air, eyes lighting up. "Maybe it's some kind of Nazi human sacrifice." He gauged the other two's disapproving stares and shook his head again. "Yeah, never mind."

All around them was chaos. Monitors were cracked and electrical sparks flew. Agents lay unconscious or dead on the floor. The DEO employees were running around, dragging of their comrades to the med bay or moving to get bigger weaponry. Suddenly blue light filled the room. The portal was back. Agents lifted up their weapons. Mon-El took a defensive stance. "They're back."

"Wait, don't shoot!" Cisco Ramon and Caitlin Snow hopped through the portal.

The agents didn't lower their guns. Cisco looked around the base. "Are you sure this is a good idea, Cait? Looks like they've got bigger problems."

Both J'onn and Mon-El recognized Cisco from when Barry had been trapped in a musical universe with Kara Danvers. "Lower your weapons." J'onn ordered.

"Why are you here? Is Kara okay?" Mon-El asked.

"We need your help." Caitlin said.

J'onn gestured to the mess around them. "Now is not the best time."

"It's about Kara."

"What happened? Is she alright?" Winn said.

"The Nazi version of Kara is dying. She wants to cut open Kara and take her heart so she can live. We think that took her to Earth-X. They're using red sunlight to dampen her powers." Caitlin explained.

"We have some friends on Earth-X right now. They should have come back by now. If we're going to save Kara, we need all the firepower we can get." Cisco looked right at Mon-El as he said this. "Come with us, please."

Mon-El nodded. "Of course. This world needs Supergirl."

J'onn crossed his arms. "I need to stay here, deal with the damages that have been done here at the DEO. Mon-El and Agent Schott will go with you on one condition; you bring back all my agents alive, including Kara and Alex Danvers."

Caitlin nodded. 'We will do everything in our power to make sure no one gets hurt."

"Except for the Nazis." Cisco cut in. He reopened the breach. "Let's go kick some ass!"


	4. Chapter 4

**Wowza! I am bad at updating! So sorry :(**

 **Disclaimer: I don't own any part of these DC shows, this is just for fun**

 **Also I am taking some creative liberties on what everyone is doing during this crossover, everything will get progressively less and less canon**

 **Earth-X**

Sara Lance could feel the fire of the bloodlust coursing through her veins. She had gotten a handle on it since becoming a time-traveling superhero, but the sight of a Nazi version of her father marching her and the others to a public execution reminded her of her League roots. Death was no stranger to the former assassin, but she couldn't bear the thought of leaving her team to deal with Nazis and anachronisms without her.

They lined the six of them up. "Turn around." the Sturmbannfuhrer ordered.

Each of the trapped heroes turned slowly to face the soldiers holding the weapons that would take their lives. "I know you are not him, but I cannot stomach the sight," Captain Lance's doppelganger covered Oliver's face.

"READY," the soldiers advanced.

"I'm sorry, Kara." Alex Danvers whispered, her face clear of tears in her final moment.

Barry Allen's face was stricken with emotion, the utter disbelief at a speedster meeting his end at by a bullet hours after he was supposed to marry the love of his life.

"AIM," the soldiers cocked their weapons.

Sara Lance squared her jaw with the look in her eyes of someone who would meet death as an equal.

Everyone seemed to be holding their breath, even the soldiers.

"FIRE!" The gunshots echoed into the burning night sky.

Jax and Martin Stein closed their eyes together.

In the fraction of a second the bullets took to travel half the distance to their targets, blazing blue light erupted into the orange tinged sky as a breach opened. The bullets disappeared into the void and the portal closed as suddenly as it had appeared. Before anyone could react, a second portal opened.

Vibe, Killer Frost, Winn Schott, and Mon-El in his Valor suit leaped through the breach.

They disarmed and knocked out the soldiers. Mon-El delivered a crunching blow to the Sturmbannfuhrer.

"How did you know to open two breaches?" Barry gasped.

"Cisco breached us to that hill over there are we saw what was going down." Mon-El explained. "Good to see you again, Barry."

Barry was still dumbstruck. "Wish it was under better circumstances. Nice suit."

Alex shook her head. "Cutting it a little close there," her eyes found Winn, "Winn? What the hell are you doing here?"

Agent Schott held a gun, eyes wide. "At the moment, trying not to crap my pants."

Frost smirked. "We needed another nerd to figure how the hell we're going to blow that bitch up. And maybe a human shield."

Sara cocked her head. A hot meta. Nice,

Winn and Cisco removed the power dampening cuffs from the six. "This is Ray, he's going to help us." Oliver said in way of introducing the newcomer.

He nodded curtly. "We need to get back to base, fast, before anyone else comes for us," he pointed in the direction of the woods. "This way, let's go."


	5. Chapter 5

**Earth-X**

"I think our first priority is to get Kara back," Alex said.

Ray shook his head. "No, I'm sorry but we need to destroy their main command center. Your friend… I'm sorry about her."

Before Alex could properly tear Ray's face off, one of the rebels interrupted them. "General Schott? There's something you should see." They all noticed that the man was looking rather intently at Winn.

Winn's eyebrows drew together in confusion. He pointed a finger at his own chest. "Wait, me?"

Ray sighed deeply. "Connor, this is General Schott's doppelganger from Earth-38."

Connor's face turned an uncomfortable shade of red as he dipped his head awkwardly and slipped out of the room. "Whoa, I'm a general? Badass." Winn seemed pleased.

Alex rolled her eyes. "Not actually you, buddy. Now," she faced Ray and squared her shoulders. "I am not abandoning my sister."

"I'm on Danver's side," Sara agreed. Alex had enough decency to keep the blush from her cheeks as the blonde woman who had been her bed less than 24 hours ago stood up for her.

There was a collective muttering of agreement from the group. "Whatever we're going to do, we need to do it fast," said Barry.

Ray sighed deeply. "Follow me."

The legion of superheroes followed the man into a smaller subsection of the anti-Nazi headquarters. The room consisted largely of wooden table covered in papers and maps. Standing by the table was General Winslow Schott. Winn's mouth dropped open and he nudged Alex who stifled a groan. "I take it your in charge here?" Oliver said, voice low.

The more frightening version of Winn allowed his eyes to glaze over the ragtag group with obvious disdain. His eyes landed on his doppelganger, but he showed no indication of surprise. He turned to Oliver. "Yes. I hope you share none of the less redeeming qualities of your Earth-X counterpart."

Oliver bristled and Sara laid a hand on his shoulder before he could fire back a biting retort. "Ollie," she cautioned gently.

His shoulders relaxed slightly at the old nickname and the assassin continued. "I hope you have a plan to get us to this Nazi hell base, because we don't have a lot of time."

Cisco tugged Winn with him to the front of the group. "Do you have any kind of technical weapons we can take a look at? We might be able to make them _way_ better."

"All right all of you, shut the hell up. You are not my people and I have no reason to trust you. Ray. Get ready. We're launching an attack on the Fuhrer's base in 60 minutes. We're gonna blast that portal straight to hell. Those scum are gonna stay on their own god-forsaken planet." General Schott commanded.

"We need to rescue our friend," Mon-El interrupted.

"No. End of discussion. This is our only shot and I'm not throwing it away." he waved a hand and several soldiers ushered the group out, leaving Ray behind.

Alex tried to fight back but she was surprised when Killer Frost of all people pulled her back. "Cool it, girlie. We don't need to listen to that jackass. Who says we can't go on a nice murder spree of our own." she smiled, lips pulled back to show white teeth.

"Ok, no to the murder spree," Vibe shook his head. "But she has a fair point. These guys haven't been able to stop these Nazis before, who says they can do it now. There's a lot of us, I bet we can rescue Supergirl and blow up their portal too."

Barry nodded. "We need a plan."

"It's a good thing I have one then. Ok, everyone listen up," Oliver replied.

 **Earth-X- Supergirl**

She couldn't remember the last time she had been so weak. So vulnerable. The heat of the red sun lamps was unbearable. Kara couldn't get out of the restraints. Leaning cockly against the table next to her, was Overgirl. She was everything Kara couldn't stand. Overgirl smiled cruelly, red lips stark against her pale skin. Despite her facade, Kara knew she was getting weaker. Didn't stop her from making out with her husband which was disturbing enough to make Kara want to vomit.

Kara squeezed her eyes shut and thought of her mother, Astra. Kara Zor-El prayed to Rao that at the very least, she would get to see her family again.


	6. Chapter 6

**Earth-X**

Winn and Mon-El were hunched past the hill where the Nazi headquarters were. Winn was clutching a tablet as though it would keep him safe. He was monitoring the heat signatures to help notify the teams. He was also tracking the matter given off by the portal to see if any Nazi squadrons disappeared to another Earth. Mon-El was there to make sure nothing bad happened Winn. Oliver, Sara, Alex, and Killer Frost were on the hunt for Supergirl while Barry, Vibe, Oliver, and Firestorm distracted the army by the front gates.

The Supergirl group had snuck around the back of the compound. Killer Frost froze the heavy steel door so that the Arrow could blast it off. The group of four rushed the gaping hole only to be greeted by a masked group of Nazi soldiers. Sara whipped out her staffs before delivering a roundhouse kick to the nearest Nazi. The soldier hit the ground with a heavy grunt just as an arrow whizzed by to nail another in the shoulder. Meanwhile Frost was wielding an icicle that she was using to impale varying limbs. Her blue eyes glittered with determination.

Alex was doing her best to not let her fear control her but there was a ticking clock in the back of her mind as she shot her blaster into her enemy's chest. For all she knew, her sister could be lying on a metal table as evil scientists cut out her heart. A soldier knocked Alex to the floor and aimed his gun at her head. The blaster glowed with energy but the soldier suddenly crumpled motionless to the ground. Sara Lance offered Alex a hand. "Let's go get your sister."

A pang filled Alex's heart as she remembered the fate of Sara's own sister. Lying in bed that night with alcohol in their blood and stolen kissed beneath the sheets, they had shared their sorrows. Alex knew that Sara wouldn't let Kara suffer the same end.

The team rushed down a hallway. Alarms sounded, red lights flashed. It was apparent that the group at the gate had made their presence known. Before their attack, Winn had briefed them on the layout of the facility based off of blueprints he had stolen from his doppelganger's desk. They dipped down a short side hallway. A huge set of glass doors lay before them. Behind the doors were thin white curtains.

Alex led the way. They were met with heat and red light. Red sun lamps. Before them were fourth people. Evil Oliver Queen, Overgirl lying on a metal table very much awake, and Supergirl unconscious beneath the lamps. A masked man stood over Kara with a scalpel in hand.

Alex screamed and the man stepped back startled. Oliver let an explosive arrow fly, detonating the power source that charged the lamps. Dark Arrow growled and launched himself at his doppelganger. A Nazi squadron emptied into the room and Sara Lance threw herself into the midst of them. Alex pulled out her gun and let loose. Killer Frost sealed the doors with ice to prevent anyone else from getting in before blasting Dark Arrow away from stabbing Oliver's leg with a short blade.

Agent Danvers knocked out several Nazi soldiers on her way to her sister. She ripped the restraints off of Supergirl. "Kara!" she cried. "Wake up!"

Alex narrowly dodged a blast from a Nazi. In response, she aimed a shot straight into his heart. Sara was weaving her way nimbly between the remaining soldiers, landing a blow here and there. There were more bodies on the ground than standing upright. It seemed that the good guys had the upper hand. Victory was in sight. Then a cry split the air and the heroes turned to see Dark Arrow's hands wrapped around Caitlin Snow's neck. The lack of oxygen had suffocated Killer Frost. "One wrong move and I snap her neck! Drop your weapons."

Sara and Oliver lifted their hands in a surrender pose. Oliver's bow clattered to the floor. Alex glanced at her still unmoving sister before she dropped her gun. Overgirl laughed and lifted herself off of the table. She moved towards her husband.

Dark Arrow tightened his grip on Caitlin's neck. He was choking her. She was letting out small agonal gasps. She couldn't breath. Tears leaked from her eyes as her vision swam with darkness. She could feel herself losing consciousness. In the back of her mind a cool voice whispered. _Fight_.

Suddenly Killer Frost took control; she closed the inches wide gap between their faces as she pressed her icy lips to Dark Arrow's. His eyes widened in shock as the life was drained out of him. His face turned a sickening purple. His eyes glazed over and his cold figure hit the floor. Killer Frost wiped her lips with the back of her hands. She glared down as the still form with contempt. Behind her glowing eyes was a thin veil of shock. This was the first life she had ever taken. Her frozen heart took a shuddering beat before a slick smile curved her lips. She felt nothing for this man, no sympathy. In fact, she would kill that Nazi scum a thousand times over again.

An anguished cry filled the room as Overgirl collapsed in despair. Her husband was dead. She turned her gaze to Frost and her eyes glowed a dangerous red. Her mouth twisted into a snarl. Oliver grabbed his bow and notched an arrow to stop her but Overgirl hurled the medical table at him.

Heat filled the room as two lasers hit their target.


End file.
